From: Josh Berkus <josh@agliodbs.com>
To: Kai Hessing <kai.hessing@hobsons.de>
Cc: pgsql-sql@postgresql.org
Subject: Re: can a function return a virtual table?
Date: Sat, 23 Apr 2005 11:00:56 -0700
Message-ID: <200504231100.56375.josh@agliodbs.com> (raw)
In-Reply-To: <3c4m1vF6b6e6aU1@individual.net>
References: <3c4m1vF6b6e6aU1@individual.net>
Kai,
> It would be much nicer to have to write something like: SELECT xyz, abc
> FROM active(tablex); where the function 'active(x)' returns a virtual
> table with all entries from table x where status is > -1. But sadly I
> have no idea how write such a function. Good old O'reilly can't help (or
> i'm to dumb *g*).
http://techdocs.postgresql.org/guides/SetReturningFunctions
Beware, though, that query plan estimation for SRFs is less accurate than for
regular subqueries, so you could end up with unnecessarily slow query
execution. Test!
--
Josh Berkus
Aglio Database Solutions
San Francisco
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-sql@postgresql.org
Cc: josh@agliodbs.com, kai.hessing@hobsons.de
Subject: Re: can a function return a virtual table?
In-Reply-To: <200504231100.56375.josh@agliodbs.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox